A balanced resonant pressure sensor

✍ Scribed by Erik Stemme; Göran Stemme

• Publisher: Elsevier Science
• Year: 1990
• Tongue: English
• Weight: 936 KB
• Volume: 21
• Category: Article
• ISSN: 0924-4247
• DOI: 10.1016/0924-4247(90)85067-e

✦ Synopsis

A new type of resonant pressure sensor m srhcon IS described The pressure sensrttve part conststs of a square dual-diaphragm cavity structure which vibrates m a balanced torsronal mode The selected torsronal mode m combmatron with a suspensron along the two crossing node lines of the electrostatrcally vibrated part yields a htgh Q factor of 2400 m an and 80 000 m a vacuum The pressure sensitivity is a result of a pressure change-induced flexure of the two diaphragms which changes the torsional strffness and hence the resonance frequency The pressure sensttrvtty of the dtfferentral and absolute pressure sensor was 19%/bar and 14%/bar respectrvely The basic structure showed an inherent uncompensated low temperature sensttrvrty of -16 ppm/"C The fabncation process mvolvmg amsotroprc srhcon etching and silicon thermal bonding IS described The improved design which increased the Q factor m au to 3300 IS also presented